Field of the Invention
Embodiments of the present disclosure generally relate to power conversion and, more particularly, to a method and apparatus for paralleling multiple low-power battery cells.
Description of the Related Art
Battery systems are used in a large variety of applications for providing a source of power as well as energy storage. In addition to DC battery systems which provide DC power, there are also AC battery systems which provide AC power.
Conventional AC battery systems provide AC power via one or more DC-AC inverters coupled to the DC output from one or more rechargeable batteries, where each battery is composed of multiple battery cells connected in both series and parallel configurations. Although a battery management system (BMS) may be used for managing such AC battery systems by monitoring operating parameters of the battery system and controlling the battery system operation, such solutions are expensive and these AC battery systems still suffer from issues that result from the topology of the battery cell connectivity. For example, a single battery cell that is degraded may cause result in degraded power output from the battery, or may cause another cell within the battery to overcharge and result in damage to the battery. Additionally, cell mismatch can create safety dangers, such as fires or explosions. Such mismatch is increasingly difficult to manage as the size of the array increases.
Therefore, there is a need in the art for a battery system that can be simply and efficiently managed.